The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation. Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A186724 Number of connected regular graphs with n nodes and girth at least 4. 19

%I

%S 1,1,1,0,1,1,2,1,4,1,10,3,37,32,340,1608,18020,193907,2867725,

%T 32674058,1581632114,6705889824

%N Number of connected regular graphs with n nodes and girth at least 4.

%H Jason Kimberley, <a href="/wiki/User:Jason_Kimberley/C_girth_ge_4">Connected regular graphs with girth at least 4</a>

%H Jason Kimberley, <a href="/wiki/User:Jason_Kimberley/C_k-reg_girth_ge_g_index">Index of sequences counting connected k-regular simple graphs with girth at least g</a>

%F a(n) = sum of the n-th row of A186714.

%Y Regular graphs, of any degree, with girth at least 4: this sequence (connected), A185214 (disconnected), A185314 (not necessarily connected).

%Y Connected regular graphs of any degree with girth at least g: A005177 (g=3), this sequence (g=4), A186725 (g=5), A186726 (g=6), A186727 (g=7), A186728 (g=8), A186729 (g=9).

%Y Connected k-regular simple graphs with girth at least 4: this sequence (any k), A186714 (triangle); specified degree k: A185114 (k=2), A014371 (k=3), A033886 (k=4), A058275 (k=5), A058276 (k=6), A181153 (k=7), A181154 (k=8), A181170 (k=9).

%K nonn,hard,more

%O 0,7

%A _Jason Kimberley_, Sep 04 2011

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified January 29 04:57 EST 2020. Contains 331335 sequences. (Running on oeis4.)